SAN DIEGO -- Saul Griffith drives a hybrid car and thought he was practicing a sustainable lifestyle at his home in San Francisco.


But then he decided to calculate his carbon footprint, a measurement of greenhouse gases generated to support his lifestyle.

He was distraught to discover how unsustainable his life was.

"I was shocked," said Griffith, an inventor who recently received a coveted MacArthur Fellowship and is co-founder of the Web site www.instructables.com.

Technology can play a critical role in helping Americans understand the challenges posed by global warming and help them make changes to reduce its threat, Griffith told several hundred people Tuesday at the annual Emerging Technology Conference organized by Sebastopol publisher O'Reilly Media.

The three-day conference is intended to bring together pre-eminent scientists from many disciplines and let them share the latest technology and ideas from their fields. On Tuesday, many of them addressed climate change and what needed to be done to create a sustainable global economy.

Griffith calculated his energy consumption in kilowatts, and included everything from his share of the federal government's power usage to the amount of energy required to make the bottle of water he drank for breakfast.

"If I drink one bottle of water, it contributes about 4 percent of my allowable energy use a day," he said.

He realized he needed to cut his energy consumption to one-tenth its current level.

"In some respects, I was really depressed. But on the other hand it was great, because now I know what I need to do," he said.

Other scientists are fighting global warming by searching for ways to reduce power consumption or make computers more energy-efficient.

"If our cars were as inefficient as computers, we would only be able to travel a few kilometers on a full tank of gas," said Stan Williams, one of five senior fellows at Hewlett-Packard Laboratories.

Williams and other scientists at H-P Labs are conducting research to reduce the amount of energy used by computers, and also to reduce the energy and materials required in making computers.

"Our calculations go all the way back to include the extraction of the raw materials to be used in the product," Williams said. "It is understanding the true cost that will inform all the research we do in terms of how we make our products going forward."

During his keynote speech Monday, Tim O'Reilly, co-founder of O'Reilly Media, urged conference attendees to work on these problems.

"We may get defeated, but let's go down fighting," he later said.

One difficulty scientists face is finding the right language to express energy usage to consumers, Griffith said.

To illustrate his point, he used an analogy comparing our daily caloric intake to our daily energy use.

Figuring out the number of calories in a bottled beverage is easy -- it's on the label, he said. But trying to determine how much energy was required to make that beverage and ultimately consume it is a lot trickier.

"We can change our diet because people tell us how," Griffith said. "We can't change our energy use because no one is telling us how. We don't have the right language yet."

Griffith spent three weeks researching how much energy goes into consuming everyday products.

"To have the New York Times delivered three times a week is 42 watts," he said. "Drinking two glasses of wine a day is 80 watts."

His goal is to reduce his energy consumption from about 25,000 watts to 2,200 watts. A large percentage of the energy he uses comes from traveling -- in particular flying back to his native Australia and to give lectures worldwide. Now he plans to cut back on his energy use by taking the train back from San Diego to San Francisco after the conference is over Thursday.

But the only reason he knows how much energy each mode of transportation uses is because he calculated it. Griffith believes companies should be required to disclose how much energy a product uses.

"You have to make the tools available so that people can measure their impact," he said.

You can reach Staff Writer Nathan Halverson at 521-5494 or nathan.halverson@

pressdemocrat.com.